During the Edo period, Kaminoseki, which thrived as a vital hub for maritime traffic, is where you'll find "Hatoko-no Yu". This picturesque location is said to have healed the fatigue of many travelers. The spring water, drawn from a depth of 1,000 meters underground, is rich in iron and manganese. When exposed to air, it changes color, earning it the name "Akayu" or "Crimson Hot Spring". From the open-air bath overlooking the Kaminoseki Strait in the Seto Inland Sea, you can take in the breathtaking view while feeling the pleasant breeze and listening to the soothing sound of the tides. Inside the bathhouse, which circulates hot spring water, you'll find creatively designed "Stone Bath" and "Wood Bath", both boasting an impressive ceiling height of 8 meters.